WORK-RELATED ASTHMA:

• Michael Pysklywec, MD MSc CCFP(EM) DOHS FCBOM

Occupational Health Clinics for Ontario Workers

McMaster University, Department of Clinical Epidemiology & Biostatistics

• Sonia Lal CRSP, RPIH

Clinical Occupational Hygienist/Health & Safety Specialist

Occupational Health Clinics for Ontario Workers

Partnerships

Objectives for industry workers and managers

Upon completion of this session, participants should be able

to:

• Gain understanding about the hazards which cause WRA

(work-related asthma)

• Recognize WRA in working adults with new-onset asthma, or

a recent deterioration of existing asthma

• Know where to go for treatment

• Assist workers to reduce or prevent workplace exposures by

good work practices

• Understand the initiatives for PREVENTION of work-related

asthma in workplaces.

Have you ever seen a case of work-related

asthma?

1. Yes, many.

2. Yes, a few.

3. Possibly, I’m not

sure.

4. Never.

1. 2. 3. 4.

0% 0%0%0%

What is your occupation?

1. Physician

2. Nurse

3. Pharmacist

4. Respiratory Therapist

5. Health and Safety

professional

6. Worker

7. Union officer

8. Joint Health and Safety

Committee Member

9. Other

1. 2. 3. 4. 5. 6. 7. 8. 9.

0% 0% 0% 0%0%0%0%0%0%

Epidemiology

How much adult asthma is related to

work?

1. 1 - 2 %

2. 10 – 25%

3. 50%

4. 80%

1. 2. 3. 4.

0% 0%0%0%

Canadian Prevalence of WRA • Johnson et al, 2000

• 7% (27/383) of all asthmatics had probable OA (healthcare, hairdressers, baker, agriculture)

• 16% (60/383) had probable or possible OA

• Tarlo et al, 2000

• 7% (51/682) of all asthmatics had asthma that was worse at work 25/51 (49%) were thought to have work-related aggravation of

their asthma (second-hand smoke, stress, paint, dust, etc.) 16/51 (31%) were thought to have sensitizer-induced OA

(cedar, isocyanates, grain, flour, hairdresser, etc.) 10/51 (20%) were possible OA/aggravation (flour, rubber,

metal plater, carpenter, etc.) None had irritant-induced OA

International data • Kogevinas, Zock, Jarvis et al, Lancet 2007 - A study with 7000

participants in 13 countries showed a population attributable risk (PAR) of OA between 10 - 25%

• Toren, Blanc, BMC Pulm Med 2009 – systematic analysis showed PAR of 16.3%

Holness et al, 2007

• Survey of 65 respirologists and 600 family physicians in

Ontario

• 92% of respirologists and 57% FD’s reported taking occ.

history “always/most” of time

• Barriers to not obtaining work history:

Spec. FD

Time constraints 60% 86%

Lack of knowledge of WSIB 60 74

Forget to ask 40 67

Patients unable to provide 40 47

Poonai et al, 2005

• Surveyed 42 patients with OA to examine factors that delayed diagnosis (Toronto)

• Mean time to diagnosis = 4.9 years

• Length of time from symptom onset and reporting of symptoms = 0.61 years

Physician did not ask about work-relatedness 41%

Afraid of lost work time 37.5%

Afraid of forced job loss 33%

Underestimation of symptoms by patient 27%

Patient did not reveal that symptoms worse at work 18%

Work-related asthma is not

uncommon (10-25%) but often

under-recognized

Classification

What is asthma?

• Chronic lung disease affecting over 3 million Canadians

• Three hallmarks:

• Reversible

• Airway inflammation (swelling)

• Airway constriction (tightening)

• Brought on and aggravated by certain triggers (family

history, allergy, allergens, infections, smoking, etc.)

Work-related asthma (WRA)

Occupational

Asthma

Work-exacerbated

Asthma (WEA)

Sensitizer-induced

(allergic)

Irritant-induced

(reactive airways

dysfunction syndrome:

RADS)

Work-related asthma (WRA)

Occupational

Asthma

Work-exacerbated

Asthma (WEA)

Sensitizer-induced

(allergic)

Irritant-induced

(reactive airways

dysfunction syndrome:

RADS)

• Represents the majority of occupational asthma (>90%)

• Clinical features:

• fulfils the classic criteria for an allergic response:

asthma usually occurs in a minority of those exposed

asthma develops only after an initial symptom-free period of exposure

• latency period of sensitization may be weeks to many years

• Symptoms worsen at work or shortly after work

• Symptoms improve when away from work (initially – if exposure continues, improvement away may not happen)

Sensitizer-induced occupational asthma

Which of the following work exposures may

cause sensitizer-induced occupational asthma?

1. paint hardeners

2. iron dust

3. nickel dust

4. flour

5. metalworking fluids

6. talc

7. animal dander

1. 2. 3. 4. 5. 6. 7.

0% 0% 0%0%0%0%0%

Sensitizers • There are over 300 known sensitizers, with more every year

• high molecular weight – generally proteins

e.g. latex, flour, animal dander

more likely to act as antigens through an IgE mechanism

• low molecular weight – generally chemicals

e.g. isocyanates, metals

pathophysiology of mechanism is not well understood

• at particular risk are those with general risk factors for asthma:

• Atopy, co-existing infections

Bakers

• allergens: cereal flour (wheat, rye,

barley), enzymes, contaminants

(alternaria, athropodes, aspergillus,

dust mites) (Brant 2007)

• High prevalence: between 5 to 24%

of subjects may be affected

• Asthma is commonly preceded by

rhinitis

• IgE-dependent mechanism

• Skin prick testing in diagnosis of

baker’s asthma (Sander, 2004):

• Sensitivity of 40 and 67%,

respectively for wheat and

flour sensitization

Case

• A review of Mrs. L’s workplace indicated unavoidable

exposure to grain dusts

• Various grains are used in her industry: wheat, rye, oats

• Various enzymes are used in the industry

• There was obvious presence of potential sensitizers;

determining which was causing the problem was difficult

Painters

• Isocyanates, (also chromium salts, epoxies)

• Approximately 5% of exposed subjects develop OA (note: may also see IIA)

• Isocyanates are also direct irritants to the respiratory tract—significant exposure can cause fatality (?Bhopal)

• Immunological mechanisms involving IgE and IgG have been demonstrated but not consistent (Liu et al, 2003); immunologic testing in humans is of variable use (Tarlo et al, 2008)

• Asthma often develops fairly quickly

• it is marked by its severity and persistence once established

Metal-workers + metal working fluids • e.g. vanadium, chromium, nickel,

platinum, palladium

• For platinum, prevalence was

originally very high (>50% of

exposed subjects); with appropriate

precautions in the work place this

figure is now 10%.

• Most sufferers are atopic

• Exposure group may include:

chemists, electronics industry,

photographers, smelters

Hairdressers (henna, sericin, persulphates)

• Henna, persulphates (oxidizing agent in hair bleach), sericin (hair spray), latex

• strongly associated with atopic subjects

• combination of exposure to irritants and allergens in a work place which is typically poorly ventilated

• Third most common cause of OA in France (Ameille, 2003), behind bakers and painters

Health care workers

• Previously latex

• the proportion of hospital

personnel reported as being

sensitized to latex varies from

3% to 12%

• Reaction to natural latex protein

• IgE-dependent mechanism

• cross reactivity has been

demonstrated between latex,

banana, chestnuts and kiwis

• Asthma in the work-place

frequently associated with

pruritus and ENT symptoms

MANY OTHER INDUSTRIES Industry specific booklets and fact sheets at the Ontario Lung Association booth and downloadable on the website.

http://www.on.lung.ca/work-related-asthma

NEW worker education web-based tool at

http://lung.ca/workrelatedasthma/

Work-related asthma (WRA)

Occupational

Asthma

Work-exacerbated

Asthma (WEA)

Sensitizer-induced

(allergic)

Irritant-induced

(reactive airways

dysfunction syndrome: RADS)

Irritant-induced occupational asthma

• Represents a small fraction of OA (approx. 6%)

• Onset typically occurs within 24 hours of exposure to a large quantity of a respiratory irritant. That is, unlike sensitizer-induced OA, there is typically no latency period.

• Most will recover after a toxic inhalation injury; some do not

• There is persistence of symptoms beyond 12 weeks, possibly lasting years

• Pulmonary testing shows objective evidence of asthma

• There is some evidence to suggest that chronic, low-level exposure to irritants (dusts, gases, mists, fumes, smoke) that are irritating to the respiratory tract may cause asthma (Balmes 2002)

Work-related asthma (WRA)

Occupational

Asthma Work- exacerbated /

aggravated Asthma

(WEA)

Sensitizer-induced

(allergic)

Irritant-induced

(reactive airways

dysfunction syndrome:

RADS)

CAUSES Work-Exacerbated Asthma

(also called work-aggravated asthma)

• Exposure to workplace irritants or exertion at work may aggravate pre-existing or concurrent asthma, particularly in patient who have moderate or severe asthma, or who are uncontrolled, because they are not receiving optimal treatment.

• Work-exacerbated asthma represented approximately half of work-related asthma seen in a Canadian clinic studies (Tarlo, 2000).

• People with pre-existing asthma are still susceptible to sensitizers in the workplace

Diagnosis: a multi-step process

1. DIAGNOSE ASTHMA

2. SUSPECT WORK-RELATEDNESS

3. DETERMINE WORK-RELATEDNESS

Suspect work-relatedness!!!

• Careful history is key:

• Are symptoms worse at work?

• Did symptoms start in adulthood/with job change?

• Are they in a high risk industry (e.g. painting, baking,

health care)?

• Are others similarly affected in the workplace?

• Are symptoms related to unusual episodic exposures

such as:

a) chemical releases or building renovations?

b) the introduction of new processes or materials?

Suspect work-relatedness:

Identify sensitizer or causative agent

• MSDS from worker: look for respiratory sensitizers

• Speak with employer/occupational health nurse

• Literature review of exposures

• OLA Asthma Triggers booklet

• OLA industry-specific information

• Specialist referral

• OHCOW: access to occupational hygienists and

physicians

• St. Michaels Occupational Health Clinic

Determine Work-relatedness Tarlo et al, 2008: ACCP Consensus Statement on WRA

• Consider objective testing (particularly when working):

Serial peak flow measurements

Serial methacholine

Immunologic assessments

Induced sputum

Specific inhalation challenge

• May require specialist (respirologist) referral

Serial peak flow

• Serial peak flow measurements (QID, 2 weeks on and off)

Peak Expiratory Flow Rates (PEFR) • Careful instruction (effort

dependent, need good technique)

• Self-record by patient in triplicate at least 4 times a day (pre-work, mid-shift, post shift, bedtime) on work days and similar times off work.

• Also record symptoms and prn medication use.

• Keep regular meds stable at the lowest dose to adequately control symptoms but not to mask PEF changes

• Record at least 2 weeks at work and 10 days off work

Management of WRA

The three main components of the management of

WRA are:

1. Treat the asthma as per the usual guidelines

2. Address issues of workplace exposure

3. Initiate compensation claim, if applicable

What is the best management option for a patient

with confirmed sensitizer-induced occupational

asthma?

1. N95 mask

2. High-efficiency

local ventilation to

process

3. Optimize use of

inhaled steroid and

bronchodilator

4. Remove from work

1. 2. 3. 4.

0% 0%0%0%

Management of WRA

• OA (sensitizer-induced)

• Remove from exposure:

Longer duration of exposure leads to increased risk of

permanence and increased severity of disease

Workers can react to very small amounts of exposure

• Irritant induced asthma (RADS)

• Remove from work until symptoms resolve

• Return to work should be considered a trial – may react to

exposures for long period (some cases up to 2 years)

• Work Exacerbated Asthma (WEA):

• Control exposure - engineering efforts, modified work

• Respirator is not a solution

Management of WRA

• Initiate a compensation claim; see the WSIB site for

physician forms

• Sentinel health event: consider that others may be

similarly affected

• All workers need education and information about

managing their asthma, recognition of triggers and what

to do about them + + + support.

• Employers and workplace parties also need this

information as well as support in determining how they

will manage the worker and address exposure issues

Is work exacerbated asthma compensable

under WSIB?

1. Yes

2. No

1. 2.

0%0%

Outcomes and Impact of Work Related

Asthma

Expectations of the Workplace

• Provide modified work for worker removed from exposures

• Encouraged by WSIB to get worker back to work as early as possible

• This may not be straight forward if exposure not well understood

E.g. where is it in the plant, how is it getting to the worker, how much can worker be exposed to

• If not possible – worker will remain off

• Workplace should assess exposures

Ongoing exposure to an allergen at work can lead

to permanence of asthma even after leaving the

workplace?

1. True

2. False

1. 2.

0%0%

Health Effects

• Majority of workers continue with symptoms and functional abnormalities even after removed from exposure

• Airway inflammation can persist long after stopping exposure and can become permanent

• OA -maximum improvement in the first 2 yrs once removed from exposure – still improvement but slower

If worker is sensitized, s/he can react to very very small amounts of substance – even below detectable levels

Irritant induced – symptoms may persistent for months and years after exposure

Outcome of OA

• Systematic review of outcome of OA after cessation of

exposure

• Pooled estimate of rates of recovery was 32% (95% CI = 26

to 38%)

• Lower recovery with increasing age

• Shorter duration of exposure correlated with greater chance of recovery

• HMW agents were associated with greater risk of persistent bronchial hyper-reactivity

Rachiotis et al, 2007

Gannon et al, 1993

• UK follow-up study on workers with OA

• 32% continued to have exposure

• These workers had ongoing decline in PFT’s

• Median loss of income = 35%

• 68% were removed from exposure

• Median loss of income = 54%

• FEV1 improved by 4.6%

• Greater symptomatic improvement than those still exposed

• Significant physiological, vocation, social, psychological consequence of WRA

Implication of WRA

Prevention

PRIMARY PREVENTION STRATEGY

Occupational Disease Iceberg:

Occupational Disease Iceberg:

MONITORING AND CONTROL

Source Path Worker

elimination

substitution

isolation

engineering

maintenance

local ventilation

air direction

distance from

source

barriers

change in work

process

isolation

job rotation

training & education

personal protective

equipment (PPE)

•

Primary Prevention (eliminate/reduce exposure)

Most effective Least effective

50

Prevention Strategy –

General Guidelines for Exposure Control

1 • Identify

2 • Eliminate

3 • Substitute

4 • Engineering Controls

5 • Administrative Controls

6 • Personal Protective Equipment

7 • Exposure-monitoring program

8 • Continual Improvement

T

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&

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HOW DO WE IDENTIFY EXPOSURES

THAT NEED TO BE CONTROLLED?

Characterize Exposure Setting

• Systematic review of the

• processes (chemical changes through processes)

• materials (MSDS, chemical research, consult with suppliers, etc.) chemical behaviour and properties

• practices consider housekeeping methods (dry versus wet)

consider bystander exposures

• controls

Occupational Health Team can be of paramount importance to a

workplace, in the identification and control of exposures/hazards.

1. IDENTIFY

1. Characterize the Exposure Setting 2. Identify Exposure Pathways

Bystander

Exposures

2. Identify Exposure Pathways

i. Chemical Behaviour/Properties (refer to MSDS, Chemical Research,

Occupational Health professionals)

• Physical State

• Odour Threshold

• Volatility

• Vapour Pressure

• Density

• Specific Gravity

1. IDENTIFY

HSE - 2003

Research

• Study the chemical components (chemical name –CAS #)

• IARC (International Agency for Research on Cancer)

• ATSDR (Agency for Toxic Substances and Disease Registry)

• IPCS –(International Programme on Chemical Safety)-INCHEM

• CCOHS (Canadian Centre for Occupational Health and Safety)

http://ccinfoweb.ccohs.ca/cheminfo/search.html

• NIOSH (National Institute for Occupational Safety and Health)

• http://hazmap.nlm.nih.gov/

56

1. IDENTIFY

Plog, Fundamentals of

Industrial Hygiene

Injection

Exposure Assessment Framework:

1. IDENTIFY

C

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t

r

o

l

s

Isonel 51-

Epoxy Resin

2. Identify Exposure Pathways iii. Chemical Changes

•Cable Insulator/Welder – 24 months with new employer:

•uses Isonel 51 (VPI tank), to coat cables and welds these coated

cables to other components

•Presents with an unexplained rash and blistering on forearms,

hands and groin area. Physician provides steroid crème and anti-

itch medication (pills) and sends patient home.

1. IDENTIFY – Case Study #1

Case Study

•Weeks later the patient continues to exhibit

signs of rash on forearms, hands, groin area

and other areas as well

•Complains of asthma like symptoms,

rhinitis and wheezing when watching TV at

home in the late evenings.

•Hay fever?

•Co-workers also exhibit signs of rash and

respiratory challenges, some of which start

reacting as soon as they walk to their work

stations, past the Isonel Dip tank, at the start

of their shift.

What should be a plausible next step(s) in this

situation?

1. Employees should inform supervisor of their symptomology and request MSDS for the products they work with

2. Take the information to an Occupational Health Clinic for further diagnostic investigation

3. Seek medical attention and show Dr. MSDS

4. Not work related – as the patient may have allergies

5. All of the above – except 4?

Em

ploye

es s

hould

in...

Take

the

info

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0% 0%0%0%0%

Isonel 51 Formaldehyde Heat (Welding, Ovens)

2. Identify Exposure Pathways

c. Chemical Changes

Chemical Changes

1. IDENTIFY Case #1

Isonel 51 Formaldehyde Heat (Welding, Ovens)

Trichloroethylene Heat (Welding, Ovens) HCL

BisChloromethyl Ether - Lung Carcinogen

2. Identify Exposure Pathways

c. Chemical Changes

Chemical Changes:

1. IDENTIFY Case #1

MSDSs will clearly indicate the presence of a

respiratory sensitizer.

1. True

2. False

1. 2.

0%0%

Common asthma related statements on MSDSs:

The product is a respiratory tract sensitizer or causes

respiratory sensitization,

Asthma is a possible health effect

Some potential sensitizers/irritants may not be listed on the

MSDS.

WHMIS requires that any sensitizer be listed as hazardous if

it is present at concentrations of 0.1% or greater.

May cause respiratory sensitization

-asthma may not be listed as a possible health effect, thus

more in depth information would be required

Is a respiratory irritant and/or can cause asthma-like

symptoms

1. IDENTIFY

Many hazardous agents’ exposure levels are regulated by Occupational

Exposure Levels (OEL) in Ontario for example, which quantify levels to

determine:

• if controls are adequate

• If the workplace is within compliance of regulations

Examples:

A) Ontario Regulation 833

Sets out specific occupational exposure limits;

(B) Ontario Designated Substances

Critical Importance:

• Sensitizer levels need only be minimal for exacerbation of symptoms.

• Exposure levels of sensitizers are difficult to quantify – when

variable/intermittent

• Sensitization or symptoms may still occur despite respirator usage (or in

a setting where exposures are within limits)

1. IDENTIFY

Which of the following are effective hygiene

controls in preventing occupational asthma (all

that apply)?

1. Product elimination

2. Product substitution

3. Engineering

controls, such as

local ventilation

4. PPE

1. 2. 3. 4.

0% 0%0%0%

Prevention Strategy –

General Guidelines for Exposure Control

1 • Identify

2 • Eliminate

3 • Substitute

4 • Engineering Controls

5 • Administrative Controls

6 • Personal Protective Equipment

7 • Exposure-monitoring program

8 • Continual Improvement

T

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The Substitution may involve:

Changing the form of the product

Ex. choose liquid formulation of a product rather than a powder, as this prevents the release of fine dusts into the air

Note: The same critical process of reviewing the new “substitute” should be implemented.

68

3. Substitute

Ontario Lung Association – Work Related Asthma Brochure

Prevention Strategy –

General Guidelines for Exposure Control

1 • Identify

2 • Eliminate

3 • Substitute

4 • Engineering Controls

5 • Administrative Controls

6 • Personal Protective Equipment

7 • Exposure-monitoring program

8 • Continual Improvement

T

r

a

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i

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Localize/Generalize/Centralize:

Local exhaust ventilation Take toxic air away from the worker’s

breathing zone

Improve general ventilation in all work areas where there are uncontrolled exposures to fumes, smoke, dusts and other irritants or common allergens

Centralize areas where sensitizers are used to a few key locations and isolate or enclose those areas; provide local exhaust whenever possible.

Safe Enclosures

ILO, http://actrav.itcilo.org/actrav-english/telearn/osh/hazard/controll.htm

4. Engineering Controls

Local Exhaust Ventilation

MAINTENANCE OF THESE CONTROLS IS OF CRITICAL IMPORTANCE IN THE PREVENTION OF OCCUPATIONAL ILLNESS

Nail Salon Workers

http://www.asianfortunenews.com/article_0113.php?article_id=46

Local Exhaust Ventilation

Division of Applied Research and Technology Engineering and Physical

Hazards Branch EPHB Report No. 005-164

September 2012

DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease

Control and Prevention National Institute for Occupational Safety and Health

Downdraft Table

Division of Applied Research and Technology Engineering and Physical Hazards

Branch EPHB Report No. 005-164

September 2012

DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease

Control and Prevention National Institute for Occupational Safety and Health

http://cleanairmadesimple.com/?p=169

In order to control exposures, an employer spends

the entire company budget of 45000$ on new

ventilation equipment. This will protect the

employees from respiratory disease permanently.

1. True

2. False

1. 2.

0%0%

Monitoring the Effectiveness of Controls • Is the hazard contained?

• Any new hazards created by the control(s)?

• Have workers been informed/educated on the hazards and

the implemented controls?

• Did maintenance staff receive training on the new

equipment for controls?

• Is there a preventative maintenance program in place?

4. Engineering Controls

Prevention Strategy –

General Guidelines for Exposure Control

1 • Identify

2 • Eliminate

3 • Substitute

4 • Engineering Controls

5 • Administrative Controls

6 • Personal Protective Equipment

7 • Exposure-monitoring program

8 • Continual Improvement

T

r

a

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&

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PPE is the last line of defense • should not be the only method of exposure control

when exposures are ongoing and cannot be prevented or significantly reduced by elimination, substitution or engineering/administrative controls.

Provide a detailed respiratory protection program which includes: exposure symptoms, controls proper respirator selection, training in its use, fit testing and, respirator maintenance/storage

6. Personal Protective Equipment (PPE)

Prevention Strategy –

General Guidelines for Exposure Control

1 • Identify

2 • Eliminate

3 • Substitute

4 • Engineering Controls

5 • Administrative Controls

6 • Personal Protective Equipment

7 • Exposure-monitoring program

8 • Continual Improvement

T

r

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Employers, in consultation with the workplace health and safety

committee (representative), should provide training and

education to workers to help prevent and manage work-related

asthma.

A training program should help workers to:

Identify the agents that can cause work-related asthma,

exposures/hazards related to Occupational Asthma

Understand the controls implemented and when/if they are

failing

Understand the process of reporting concerns in the

workplace and of seeking immediate medical attention.

Recognize the symptoms of work-related asthma

Follow safe work practices to reduce exposure to these agents

(inclusive of spills, handling, housekeeping etc.)

Training & Education

• Call Center employee:

• Experiencing flu like symptoms

• Unexplainable rash on face and arms

• Difficulty breathing

• Difficulty concentrating

• Increasingly absent from work

• Works in corner of 2nd floor call center (open concept offices with 25 workers) next to kitchen, restroom, and large window. Also has a skylight above this area of the office.

• Call Center:

• Newly appointed JHSC members

• Company safety department took measurements for: Carbon Dioxide, Temperature, Relative humidity, Carbon Monoxide. Results were all within normal levels except for Relative humidity (recorded at higher than normal levels) – this

was resolved immediately)

Case Study

What Should be the Plausible Next Step?

A. Consult with maintenance

B. Interview the worker

C. JHSC to conduct an investigation and interview workers

D. Consult the Occupational Health Team to get assistance with an investigation

E. All of the above

Con

sult

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JHSC to

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Case Study

Case: Health Care Industry

• Sari is a nurse working in the gastrointestinal investigation unit in an acute

care hospital.

• Job includes cleaning and sterilising medical instruments and

equipment after procedures.

• A variety of cleaning agents are used as well as gluteraldehyde for

cold sterilisation.

• Symptoms:

• tendency toward cough, undue shortness of breath, especially when

cleaning equipment.

• Symptoms also after work, on exertion and has been waking up with

coughing.

• Symptoms improved while on 2 weeks vacation

What do you think could be wrong with Sari?

1. Sensitizer induced

asthma

2. Irritant induced asthma

3. Work exacerbated

asthma

4. Work related asthma

5. She has a recurring

cold

1. 2. 3. 4. 5.

0% 0%0%0%0%

• Sari is diagnosed with sensitizer induced asthma and it is

believed that the sensitizing agent was gluteraldehyde.

• The occupational health and safety manager, recognizing that

gluteraldehyde is a sensitizer, is working his way through

“control” options and is starting at the optimum point -

exploring eliminating it from the GI unit and replacing it with

something else.

Case– Health Care

Primary Prevention

In this example, machine compatibility with the new

agent must be considered.

1. True

2. False

1. 2.

0%0%

• Work-related asthma is not rare and is often under-

recognized

• Most work-related asthma is due to sensitizers in the

workplace (similar to other occupational allergies such as

dermatitis and rhinitis)

• You play a key role in suspecting/recognizing WRA

• Those with sensitizer-induced WRA need to avoid any

exposure to exposure: often requires removal from work

• Early recognition and management is key to minimize

permanence and severity

• Preventing exposure is key to reducing incidence

REVIEW QUESTIONS

KEY SUMMARY POINTS:

How much adult asthma is related to

work?

1. 1 - 2 %

2. 10 – 25%

3. 50%

4. 80%

1. 2. 3. 4.

0% 0%0%0%

Which of the following work exposures may

cause sensitizer-induced occupational asthma?

1. paint hardeners

2. iron dust

3. nickel dust

4. flour

5. metalworking fluids

6. talc

7. animal dander

1. 2. 3. 4. 5. 6. 7.

0% 0% 0%0%0%0%0%

What is the best management option for a patient

with confirmed sensitizer-induced occupational

asthma?

1. N95 mask

2. High-efficiency

local ventilation to

process

3. Optimize use of

inhaled steroid and

bronchodilator

4. Remove from work

1. 2. 3. 4.

0% 0%0%0%

Is work exacerbated asthma compensable

under WSIB?

1. Yes

2. No

1. 2.

0%0%

Which of the following are effective hygiene

controls in preventing occupational asthma (all

that apply)?

1. Product elimination

2. Product substitution

3. Engineering

controls, such as

local ventilation

4. PPE

1. 2. 3. 4.

0% 0%0%0%

This workshop provided a clear and concise

presentation on work-related asthma.

A. Strongly Agree

B. Agree

C. Somewhat Agree

D. Neutral

E. Somewhat Disagree

F. Disagree

G. Strongly Disagree

Strongly

Agre

e

Agr

ee

Som

ewhat

Agre

e

Neu

tral

Som

ewhat

Dis

agre

e

Dis

agre

e

Strongly

Dis

agre

e

0% 0% 0%0%0%0%0%

This information on WRA will be useful to me in

my job.

A. Strongly Agree

B. Agree

C. Somewhat Agree

D. Neutral

E. Somewhat Disagree

F. Disagree

G. Strongly Disagree

Strongly

Agre

e

Agr

ee

Som

ewhat

Agre

e

Neu

tral

Som

ewhat

Dis

agre

e

Dis

agre

e

Strongly

Dis

agre

e

0% 0% 0%0%0%0%0%

With thanks to: